Alaska Airlines is a major American airline headquartered in SeaTac, Washington, within the Seattle metropolitan area. It is the sixth largest airline in North America when measured by fleet size, scheduled passengers carried, and the number of destinations served. Alaska, together with its regional partners Horizon Air and SkyWest Airlines, operates a large domestic route network, primarily focused on connecting from the Pacific Northwest, West Coast, and Alaska to over one hundred destinations in the contiguous United States, Hawaii, Belize, Canada, Costa Rica, and Mexico. The airline operates out of five hubs, with its primary hub being at Seattle–Tacoma International Airport. Alaska Airlines is a member of Oneworld, the third-largest airline alliance in the world. As of 2020, the airline employs over 16,000 people and has been ranked by J. D. Power and Associates as having the highest customer satisfaction of the traditional airlines for twelve consecutive years.